diff --git a/README.md b/README.md
index f1849f7..4e3633a 100755
--- a/README.md
+++ b/README.md
@@ -40,6 +40,7 @@ Behaviors :
 * angleArc : arc size in degrees | default=360.
 * stopper : stop at min & max on keydown/mousewheel | default=true.
 * readOnly : disable input and events | default=false.
+* rotation : direction of progression | default=clockwise.
 
 UI :
 * cursor : display mode "cursor", cursor size could be changed passing a numeric value to the option, default width is used when passing boolean value "true" | default=gauge.
@@ -131,4 +132,4 @@ Supported browser
 
 Tested on Chrome, Safari, Firefox, IE>=8.0 (IE8.0 with excanvas).
 
-![secretplan](https://raw.github.com/aterrien/jQuery-Knob/master/secretplan.jpg)
\ No newline at end of file
+![secretplan](https://raw.github.com/aterrien/jQuery-Knob/master/secretplan.jpg)
diff --git a/index.html b/index.html
index 1e17ef4..3dffa5e 100755
--- a/index.html
+++ b/index.html
@@ -24,33 +24,25 @@
                         // "tron" case
                         if(this.$.data('skin') == 'tron') {
 
-                            var a = this.angle(this.cv)  // Angle
-                                , sa = this.startAngle          // Previous start angle
-                                , sat = this.startAngle         // Start angle
-                                , ea                            // Previous end angle
-                                , eat = sat + a                 // End angle
+                            this.cursorExt = 0.3;
+
+                            var a = this.arc(this.cv)  // Arc
+                                , pa                   // Previous arc
                                 , r = 1;
 
                             this.g.lineWidth = this.lineWidth;
 
-                            this.o.cursor
-                                && (sat = eat - 0.3)
-                                && (eat = eat + 0.3);
-
                             if (this.o.displayPrevious) {
-                                ea = this.startAngle + this.angle(this.v);
-                                this.o.cursor
-                                    && (sa = ea - 0.3)
-                                    && (ea = ea + 0.3);
+                                pa = this.arc(this.v);
                                 this.g.beginPath();
                                 this.g.strokeStyle = this.pColor;
-                                this.g.arc(this.xy, this.xy, this.radius - this.lineWidth, sa, ea, false);
+                                this.g.arc(this.xy, this.xy, this.radius - this.lineWidth, pa.s, pa.e, pa.d);
                                 this.g.stroke();
                             }
 
                             this.g.beginPath();
                             this.g.strokeStyle = r ? this.o.fgColor : this.fgColor ;
-                            this.g.arc(this.xy, this.xy, this.radius - this.lineWidth, sat, eat, false);
+                            this.g.arc(this.xy, this.xy, this.radius - this.lineWidth, a.s, a.e, a.d);
                             this.g.stroke();
 
                             this.g.lineWidth = 2;
@@ -156,8 +148,9 @@ <h1>jQuery Knob</h1>
 data-fgColor="#66CC66"
 data-angleOffset=-125
 data-angleArc=250
+data-rotation=anticlockwise
             </pre>
-            <input class="knob" data-angleOffset=-125 data-angleArc=250 data-fgColor="#66EE66" value="35">
+            <input class="knob" data-angleOffset=-125 data-angleArc=250 data-fgColor="#66EE66" data-rotation="anticlockwise" value="35">
         </div>
         <div class="demo" >
             <p>&#215; 5-digit values, step 1000</p>
diff --git a/js/jquery.knob.js b/js/jquery.knob.js
index a2fb82a..c3f097a 100755
--- a/js/jquery.knob.js
+++ b/js/jquery.knob.js
@@ -110,6 +110,7 @@
                     fontWeight: this.$.data('font-weight') || 'bold',
                     inline : false,
                     step : this.$.data('step') || 1,
+                    rotation: this.$.data('rotation'),
 
                     // Hooks
                     draw : null, // function () {}
@@ -120,6 +121,7 @@
             );
 
             // finalize options
+            this.o.flip = this.o.rotation === 'anticlockwise' || this.o.rotation === 'acw';
             if(!this.o.inputColor) {
                 this.o.inputColor = this.o.fgColor;
             }
@@ -526,6 +528,10 @@
                         , - (y - this.y - this.w2)
                     ) - this.angleOffset;
 
+            if (this.o.flip) {
+                a = this.angleArc - a - this.PI2;
+            }
+
             if(this.angleArc != this.PI2 && (a < 0) && (a > -0.5)) {
                 // if isset angleArc option, set to min if .5 under min
                 a = 0;
@@ -705,45 +711,54 @@
             return (v - this.o.min) * this.angleArc / (this.o.max - this.o.min);
         };
 
+        this.arc = function (v) {
+          var sa, ea;
+          v = this.angle(v);
+          if (this.o.flip) {
+              sa = this.endAngle + 0.00001;
+              ea = sa - v - 0.00001;
+          } else {
+              sa = this.startAngle - 0.00001;
+              ea = sa + v + 0.00001;
+          }
+          this.o.cursor
+              && (sa = ea - this.cursorExt)
+              && (ea = ea + this.cursorExt);
+          return {
+              s: sa,
+              e: ea,
+              d: this.o.flip && !this.o.cursor
+          };
+        };
+
         this.draw = function () {
 
             var c = this.g,                 // context
-                a = this.angle(this.cv)    // Angle
-                , sat = this.startAngle     // Start angle
-                , eat = sat + a             // End angle
-                , sa, ea                    // Previous angles
+                a = this.arc(this.cv)       // Arc
+                , pa                        // Previous arc
                 , r = 1;
 
             c.lineWidth = this.lineWidth;
 
             c.lineCap = this.lineCap;
 
-            this.o.cursor
-                && (sat = eat - this.cursorExt)
-                && (eat = eat + this.cursorExt);
-
             c.beginPath();
                 c.strokeStyle = this.o.bgColor;
                 c.arc(this.xy, this.xy, this.radius, this.endAngle - 0.00001, this.startAngle + 0.00001, true);
             c.stroke();
 
             if (this.o.displayPrevious) {
-                ea = this.startAngle + this.angle(this.v);
-                sa = this.startAngle;
-                this.o.cursor
-                    && (sa = ea - this.cursorExt)
-                    && (ea = ea + this.cursorExt);
-
+                pa = this.arc(this.v);
                 c.beginPath();
                     c.strokeStyle = this.pColor;
-                    c.arc(this.xy, this.xy, this.radius, sa - 0.00001, ea + 0.00001, false);
+                    c.arc(this.xy, this.xy, this.radius, pa.s, pa.e, pa.d);
                 c.stroke();
                 r = (this.cv == this.v);
             }
 
             c.beginPath();
                 c.strokeStyle = r ? this.o.fgColor : this.fgColor ;
-                c.arc(this.xy, this.xy, this.radius, sat - 0.00001, eat + 0.00001, false);
+                c.arc(this.xy, this.xy, this.radius, a.s, a.e, a.d);
             c.stroke();
         };
 
@@ -763,4 +778,4 @@
         ).parent();
     };
 
-})(jQuery);
\ No newline at end of file
+})(jQuery);